The present invention relates to novel compounds having histone deacetylase 6 (HDAC6) inhibitory activity, stereoisomers thereof or pharmaceutically acceptable salts thereof, the use thereof for the preparation of therapeutic medicaments, pharmaceutical compositions containing the same, a method for treating diseases using the composition, and methods for preparing the novel compounds. The novel compounds, stereoisomers thereof or pharmaceutically acceptable salts thereof according to the present invention have histone deacetylase (HDAC) inhibitory activity and are effective for the prevention or treatment of HDAC6-mediated diseases, including infectious diseases； neoplasms； endocrine, nutritional and metabolic diseases； mental and behavioral disorders； neurological diseases； diseases of the eye and adnexa； cardiovascular diseases； respiratory diseases； digestive diseases； diseases of the skin and subcutaneous tissue； diseases of the musculoskeletal system and connective tissue； or congenital malformations, deformations and chromosomal abnormalities.本發明係關於具有組蛋白去乙醯酶6(HDAC6)抑制活性之新穎化合物、其立體異構體或其醫藥學上可接受之鹽，其用於製備治療藥物之用途，含有其之醫藥組合物，使用該組合物治療疾病之方法，及用於製備該等新穎化合物之方法。根據本發明之新穎化合物、其立體異構體或其醫藥學上可接受之鹽具有組蛋白去乙醯酶(HDAC)抑制活性且有效用於預防或治療HDAC6介導之疾病，包括感染性疾病；贅瘤；內分泌、營養及代謝疾病；精神及行為病症；神經疾病；眼睛及附件之疾病；心血管疾病；呼吸疾病；消化疾病；皮膚及皮下組織之疾病；肌肉骨胳系統及結締組織之疾病；或先天性畸形、變形及染色體異常。
